Preview in macOS Big Sur is destroying PDFs • Hacker News Board

Re: Preview in macOS Big Sur is destroying PDFs

#251

Post by abrowne » Thu, Dec 17, 2020, 1:57 AM UTC

omnimus wrote: post #231

odyssey7 wrote: post #208

Earlier quoted context omitted.

Knuth as a book author has written about this on his website. “Warning: Unfortunately, however, non-PDF versions have also appeared, against my recommendations, and those versions are frankly quite awful. A great deal of expertise and care is necessary to do the job right. If you have been misled into purchasing one of these inferior versions (for example, a Kindle edition), the publishers have told me that they will…

But thats such a specific example. Math books have so much complex notation and wierd inline elements... he had to invent TeX for that. HTML/CSS wouldn't handle it. Basically for all normal texbooks you will want epub as digital format. And if you have lot of ilustrations or wierd format book then just get the printed version.

I like PDFs for digital cookbooks as well.

Re: Preview in macOS Big Sur is destroying PDFs

#252

Post by CapriciousCptl » Thu, Dec 17, 2020, 2:01 AM UTC

birdyrooster wrote: post #41

avalys wrote: post #23

This is a clickbait, sensationalist headline. “Saving a PDF with Preview in Big Sur can corrupt OCR text added by a third-party program” is more accurate.

Did they save the file using Preview? If so that’s on them, they chose to write a pdf using Preview and that comes with all of the pitfalls of pdf compatibility. Does plain old PostScript have this problem?

Probably most people who’ve done a bit of PDF work know there’s no guarantee of the same output from different (or even the same) editor. So I don’t think it’s Preview’s fault per since the problem is endemic to PDF. But I don’t think you can blame the user either. Really, PDFs are just these enormously useful complex things that are always breaking in unexpected ways and some people haven’t been bitten by its problems enough yet to cope properly.

Re: Preview in macOS Big Sur is destroying PDFs

#253

Post by masswerk » Thu, Dec 17, 2020, 2:22 AM UTC

matrixagent wrote: post #4

zepto wrote: post #2

They are using software unsupported by the vendor and blaming Apple for the outcome. “ABBYY says they don’t support Big Sur yet, that’s fine. But Apple didn’t tell me that I can’t upgrade to Big Sur when I use ABBYY. I’d be a lot less angry if there was a changelog or release notes from Apple where it says there is a known problem with OCR’ed PDFs in Preview. Their software is broken, they need to tell me. I don’t ca…

Read it again. This bug could hit you without ever using ABBYY yourself. Apple broke Preview.

"Broke" may be a bit harsh. What appears to be happening is that Preview somehow loses or corrupts the toUnicode map, which is apparently located in the metadata, when saving the PDF. Mind that every application will have to reassemble/reflow the metadata when saving a reflowed document (like after cropping and/or discarding pages). To do so, the application has to interpret and to reassemble the metadata before wiriting it back.

Now, some algorithms and routines may be more robust and allowing than others. Maybe, an innocent refactoring attempt just lost that critical bit of robustness, required to deal with that particular format produced by this particular application.

For example, consider an XML-based format, where a particular application delivered a malformed document, like a missing closing quote for some attribute. Most XML interpreters will churn happily along with this, but, after a rewrite of some routine, an application just ignores the malformed tag with the runaway string. Did it break XML? Or did it just fail to interpret a malformed document, it had somehow been able to deal with thanks to some extra robustness present in the previous version?

Considering this hypothetical case: Should that application be improved by an update to regain its previous robustness? Yes, absolutely. Is it a bug and is the vendor to blame? Probably not. Mind that this might be quite well what is happening here, as well.

Re: Preview in macOS Big Sur is destroying PDFs

#254

Post by fomine3 » Thu, Dec 17, 2020, 2:23 AM UTC

bigbubba wrote: post #115

sildur wrote: post #86

Earlier quoted context omitted.

Blind and shortsighted people may not like your idea. There are accessibility options in PDF, but even a regular one can be accessed with a screen reader. Your images won't.

It's also generally a pain in the ass for people with good vision too, since text can't be copied out of a JPEG. If you want to forward a paragraph of text from a pure raster document, you have to read and type it all out yourself.

It's also blocker for machine translation.

Re: Preview in macOS Big Sur is destroying PDFs

#255

Post by saagarjha » Thu, Dec 17, 2020, 2:26 AM UTC

lilactown wrote: post #147

crazygringo wrote: post #48

Earlier quoted context omitted.

I personally use an iPad. It's amazing for it. Especially when you use the Apple Pencil to highlight text, make annotations like circles or question marks, etc.

I struggled to find good software for this. Is there a specific app you recommend?

PDF Viewer has worked well for me, personally.

Re: Preview in macOS Big Sur is destroying PDFs

#256

Post by CamperBob2 » Thu, Dec 17, 2020, 2:33 AM UTC

xxpor wrote: post #21

Why anyone treats PDF as anything but a write-once format is beyond me. It's so finicky that I'm not shocked bugs like this happen. The only programs I'd be reasonable sure wouldn't screw it up are Acrobat itself, and pdflatex and friends. I think we need a multi-image container format. It could be something that's literally a bunch of jpgs/pngs/pick your poison in a tar container, and given a new extension. OSes wou…

.PDF works just fine. Don't blame the shortcomings of crappy software implementations on the format itself.

We need a format that will still be readable 100 years or more from now, and .PDF serves that purpose.

Re: Preview in macOS Big Sur is destroying PDFs

#257

Post by juskrey » Thu, Dec 17, 2020, 2:35 AM UTC

Preview for PDF manipulation was a nice try at first, until I realized I suddenly have unexpected problems with produced docs, trouble with drag-and-drop, overwritten files etc..

Now I am using PDFGenius and never looking back.

Re: Preview in macOS Big Sur is destroying PDFs

#258

Post by robertoandred » Thu, Dec 17, 2020, 2:49 AM UTC

mulmen wrote: post #134

I have learned to be scared of my MacBook. Seemingly safe behavior can cause permanent damage. It does completely unexpected things, apparently by design. I do not put my pictures in the ~/Pictures directory for fear of what the newest app will do to “improve” them for me. I fully expect it to apply lossy compression to my files without asking. This is after Photos or whatever it was called at the time mangled the da…

Do you have proof of iCloud deleting photos?

Re: Preview in macOS Big Sur is destroying PDFs

#259

Post by sim_card_map » Thu, Dec 17, 2020, 2:53 AM UTC

wtallis wrote: post #186

systemvoltage wrote: post #36

Earlier quoted context omitted.

PDF is one of the best things IMO - it's like a docker container for documents. The way the original authors intended it to be, including fonts and all the things that go into making a document. For example, I personally like to purchase books that are in PDF format, not epub/mobi. I want to rely on professional typesetting from the publishers, not some front-end engineer's vision of what the ebook should look like a…

> PDF is one of the best things IMO - it's like a docker container for documents. The way the original authors intended it to be, including fonts and all the things that go into making a document. Sounds like you want the PDF/A standard for archiving: https://en.wikipedia.org/wiki/PDF/A It forbids embedding audio and video and JavaScript, requires embedding all the fonts, forbids encryption and patent-encumbered comp…

We now have JavaScript in PDFs?..

Re: Preview in macOS Big Sur is destroying PDFs

#260

Post by cratermoon » Thu, Dec 17, 2020, 3:03 AM UTC

systemvoltage wrote: post #36

xxpor wrote: post #21

Why anyone treats PDF as anything but a write-once format is beyond me. It's so finicky that I'm not shocked bugs like this happen. The only programs I'd be reasonable sure wouldn't screw it up are Acrobat itself, and pdflatex and friends. I think we need a multi-image container format. It could be something that's literally a bunch of jpgs/pngs/pick your poison in a tar container, and given a new extension. OSes wou…

PDF is one of the best things IMO - it's like a docker container for documents. The way the original authors intended it to be, including fonts and all the things that go into making a document. For example, I personally like to purchase books that are in PDF format, not epub/mobi. I want to rely on professional typesetting from the publishers, not some front-end engineer's vision of what the ebook should look like a…

What size and resolution is your eReader? I can read PDFs on my computers fine, the screen is large enough. On my eReader I can't both see a whole page and have the text large enough to read, even with my reading glasses. I end up zooming in to bring the text up to readable size and then I'm only seeing part of the page and have to scroll left/right/up/down to read a page.